7321437648domain: NAppears in sequencesa(n) = 8*a(n-1) - a(n-2); a(0) = 0, a(1) = 1.at n=12A001090Denominators of continued fraction convergents to sqrt(15).at n=23A041023Denominators of continued fraction convergents to sqrt(375).at n=23A041711Union of A057080 and A001090.at n=23A177187